HSF1A 

Protein extracts are generated from mammalian, yeast and E. coli cultures using biotin-binding buffer (20 mM HEPES, 5 mM MgCl₂, 1 mM EDTA, 100 mM KCl, 0.03% NP-40) supplemented with 1% Trition-X100 and protease inhibitors. Approximately 0.5 mg of protein extract is incubated with 100 μM HSF1A-Biotin for 4 h at 4°C and HSF1A-Biotin associated proteins captured by with NeutrAvidin Agarose Resin. After washing in biotin binding buffer proteins are eluted using 50 μL biotin elution buffer (100 mM Tris, 150 mM NaCl, 0.1 mM EDTA, 2 mM D-biotin), resolved on a 4-20% SDS-PAGE, and immunoblotted. For purified TRiC and Hsp70 analyses, 5 nM protein is incubated in biotin-binding buffer+0.5% Triton X-100 with 100 μM biotin or 100 μM HSF1A-Biotin for 4 h at 4°C and captured with NeutrAvidin Resin. For NiNTA purified yeast Tcp1, different concentrations of Tcp1 0.5 μM, 1 mM, 2 mM, 3 mM and 4 mM in 25 mM Hepes pH 7.5, 150 mM NaCl are incubated with 0.5 μM Biotin or HSF1A-Biotin for 4 h at 4°C and captured with NeutrAvidin Resin^[1].

MCE has not independently confirmed the accuracy of these methods. They are for reference only.

PC12 cells seeded into a 96-well plate (5×10⁴ cells/well) are treated with increasing concentrations of HSF1A (2, 4, 8 and 12 μM) for 15 h, at which time httQ74-GFP expression is stimulated by incubation in the presence of 1 µg/mL Doxycycline for 5 d. Cell viability is assessed via the XTT viability assay^[2].

MCE has not independently confirmed the accuracy of these methods. They are for reference only.

Rats^[3]
Ten-week-old Wistar Kyoto rats (WKY) are used. The rats are housed at a constant temperature (22°C) on a 12-h light/dark cycle with food and tap water. The animals are arranged into three groups: WKY rats (the control group), DOX rats and DOX rats treated with HSF1A. Each group contain five animals. The DOX group is injected with DOX (5 mg/kg) for 6 consecutive weeks intraperitoneal injection to achieve a cumulative dose of 30 mg/kg, which has been well documented to achieve cardiotoxicity. The small molecular HSF1 activator HSF1A (100 mg/kg/day) is injected intraperitoneally.

MCE has not independently confirmed the accuracy of these methods. They are for reference only.

• [1]. Neef DW, et al. A direct regulatory interaction between chaperonin TRiC and stress-responsive transcription factor HSF1. Cell Rep. 2014 Nov 6;9(3):955-66.  [Content Brief]

  [2]. Neef DW, et al. Modulation of heat shock transcription factor 1 as a therapeutic target for small molecule intervention in neurodegenerative disease. PLoS Biol. 2010 Jan 19;8(1):e1000291.  [Content Brief]

  [3]. Huang CY, et al. Doxorubicin attenuates CHIP-guarded HSF1 nuclear translocation and protein stability to trigger IGF-IIR-dependent cardiomyocyte death. Cell Death Dis. 2016 Nov 3;7(11):e2455.  [Content Brief]

  [4]. Marcus Steinemann, et al. The chaperonin TRiC/CCT is essential for the action of bacterial glycosylating protein toxins like Clostridium difficile toxins A and B. Proc Natl Acad Sci U S A. 2018 Sep 18;115(38):9580-9585.  [Content Brief]